6-1/2 2-way car speakers Plus One+ polypropylene woofer cone with hi-roll rubber surround 1 edge-driven, textile dome tweeter included brackets allow mounting in a variety of 6-3/4 and 6-1/2 openings True Four Ohm Impedance technology: speaker's 3-ohm impedance combines with speaker wire impedance for a 4-ohm load handles up to 55 watts RMS (165 watts peak power) frequency response: 57-21,000 Hz sensitivity: 93 dB top-mount depth: 1-13/16